"[Autonomous] systems can be used in a variety of ways," The Verge reported Cook as saying during an investor call. "A vehicle is only one, but there are many different areas of it. And I don't want to go any further with that."

Cook confirmed the existence of Apple's autonomous-driving project in June, calling it the "mother of all AI projects." The Apple CEO hasn't discussed the project in any real detail, but has said the company views it both as an important facet of the emerging AI field, and a contributor to major potential disruption in the auto industry. Like many other businesspeople, Cook reportedly believes the combination of autonomous driving, electric powertrains, and ride sharing will have an impact greater than each factor would individually.

Notably missing from all of Cook's statements on autonomous driving: any indication Apple will build its own car. The company has never said anything publicly about entering the car business, but the idea of an "Apple Car" has created a lot of excitement over the years.

It's possible that Apple will only develop the tech to enable autonomous driving, and then market it to automakers. That would be a much easier route than undertaking the expensive and complicated process of building its own car. Several other tech companies, including Waymo and Intel, have forged partnerships with automakers instead of going it alone.